Impact of Intense Geomagnetic Storm on NavIC Signals Over Indore

Abstract

Intense geomagnetic storms can have a strong impact on the signals (termed as ionospheric scintillations) emitted by any global navigation satellite system (GNSS). The paper reports the first ever scintillations at Indore region on the NavIC signals due to impact of the intense geomagnetic storm event reported on September 8, 2017 at 01:51 and 13:04 UT. The variation of the planetary indices as well as the DST index which dropped to value of −124 nT on September 8, 2017 indicates the occurrence of an intense geomagnetic storm on September 8, 2017. The observations presented are carried out at Indore, which is located at the equatorial anomaly crest. The S4 index measurements of co-located GNSS receiver showed values ≥0.5 on the disturbed day between 15 and 18 UT. The analysis presented clearly signifies the degradation of carrier–noise measurements of NavIC L5 signal during the same time, which in turn affected the positional accuracy of NavIC, an important consideration for performance. © 2021, Springer Nature Singapore Pte Ltd.